This disclosure relates generally to estimating a road grade. More particularly, the disclosure relates to estimating a road grade for a trailer vehicle that is reversing.
Towing vehicles tow trailer vehicles. A truck is an example towing vehicle. A boat is an example trailer vehicle. Both are example vehicles.
Variations in road grades may cause a trailer vehicle to exert forces in a different way on the towing vehicle. For example, when a trailer vehicle and towing vehicle are reversing, an increasing road grade may cause a trailer vehicle to exert increasing pulling force on the towing vehicle. The towing vehicle needs to account for the increasing pulling force by applying greater braking pressure for example.
When an operator of a vehicle is backing up a trailer, the operator is ordinarily able to accommodate changes in force due to variations in road grade. It may be desirable to assist an operator with these changes when backing up the trailer vehicle using an automatic backup system.